Vascular prostheses such as stents and/or stent-grafts are used for a variety of reasons in the vasculature. For example, they can be used to prop open blood vessels, treat plaque buildup, replace a portion of a blood vessel, divert blood flow away from a target area, provide a scaffold or lumen for the introduction of other medical devices, or for various other reasons.
It is desirable for these devices to have significant strength and to be able to effectively anchor within a blood vessel in order to remain expanded and to prevent migration from a target area after deployment. These devices must also be track-able through a delivery device (i.e. a catheter) without too much friction so that they can be delivered to a target site. Finally, these devices must also have some flexibility in order to conform to the shape of the vessel and mimic the natural movement of the vessels.
Stents, stent-grafts, or other vascular prostheses are sometimes formed of one or more wires that are braided into a tubular structure. When these devices are braided by hand, the wire can be braided so as to terminate along the length of the stent instead of at the stent's proximal or distal ends. As a result, the hand-braided stent's ends may be relatively smooth. However, when a stent is machine-braided, its wires must typically be cut at its distal and proximal ends, creating relatively rough/sharp stent ends. Whether hand-braided or machine-braided, sharp stent ends can cause damage to the vessels as it is deployed and therefore is undesirable.